The harvesting of onion seeds is, of course, a very old art and same has normally been carried out in the past primarily by manual methods. That is, the entire onion umbel and an adjacent part of the stalk have been removed from the plant and dried after which the seeds have been subsequently removed from the seed capsules by any appropriate means. Mechanical devices for harvesting onion seeds have in the past carried out this procedure by harvesting the entire umbel with part of the stalk which is then dried and subsequently threshed to remove the onion seed therefrom. This has necessitated the double handling, whether by hand or mechanical harvesting methods, of the entire umbel. Moreover, the debris from the umbels would have to be removed from the seed during the further handling thereof. This procedure has in the past been believed necessary in order to insure that the seed is properly matured before being separated from the remainder of the plant and further to insure the proper separation thereof.
It has been discovered, however, quite unexpectedly, that it is possible to separate the onion capsules from the umbel prior to the drying thereof so that only the capsules need to be subsequently handled and the stems of the umbels may be discharged as debris along with the remainder of the stalk. Accordingly the time for drying the capsules, by comparison with the time required for drying the capsules plus the adjacent parts of the stalk, is substantially reduced.
Accordingly, the objects of the invention include the provision of:
1. A process for harvesting onion seed wherein the seed-containing capsules are separated from the umbels associated therewith prior to the drying thereof.
2. A process, as aforesaid, which will be effective without injury to the onion seed.
3. A process, as aforesaid, in which the mechanical forces applied to the onion umbels for the separation of seed capsules therefrom are held within ranges of magnitude such that the stems supporting the seed capsules will be ruptured to release the capsules without injury to said seed capsules.
4. A process, as aforesaid, utilizing for the capsule separation step a rotating perforated drum together with a coaxially positioned rotating beater and controlling the relative speeds of said drum and beater to insure effective detachment of the seed capsules from the umbels without injuring said onion seeds.
5. Apparatus for separating seed carrying onion capsules from the umbels carrying same which will effect such separation efficiently without injury to the onion seed.
6. Apparatus, as aforesaid, which will sever the onion stalk from the ground, subject it to suitable agitation for detaching the onion capsules therefrom, will then separate the onion capsules from the stalks and parts associated therewith and discharge said seed capsules into one container while discharging the stalks and other debris elsewhere.
7. Apparatus, as aforesaid, which will be sufficiently sturdy and uncomplicated in structure as to be capable of operating under field conditions for long periods of time without excessive maintenance and without danger of excessive periods of downtime, whether such downtime is for repairs or for maintenance.
Other objects and purposes of the invention will be apparent to persons acquainted with processes and apparatus of this general type upon reading the following specification and inspection of the accompanying drawings.